1. Field of the Invention
The present invention relates to a work positioner of a chip mounter, and more particularly to techniques effective for application to a work positioner of a mounting head of a chip mounter for mounting a chip-shaped electronic part onto a substrate.
2. Related Art Statement
As a work positioner of this type, there is one constructed such that a work sucker head capable of vacuum-sucking: a work such as a chip-shaped electronic part of a semiconductor integrated circuit (IC) for example, i.e. a bit is vertically movably provided, and the work positioner is vertically movable between two positions provided in the vicinity of the bit, including one position where the work is clamped and the other position where the work is released.
In this work positioner, two pairs of positioner tips horizontally and reciprocatively movable in two directions perpendicular to each other move in states being equalized to the center of the bit, so that the work is positioned at the center of the bit.
However, the above-described work positioner suffers from the problem that the accuracy of positioning the work by the positioner tips is lowered due to shifts in angle and position, etc. Because of this, it is difficult to assemble the work positioner and it takes a long time for adjusting in the assembling work. Moreover, the above-described work positioner suffers from the problems that the number of parts is large, the construction is complicated, the working is difficult to perform, the costs are high and the maintenance properties are low.
Furthermore, for example, since the chip-shaped electronic parts include various types, it is necessary to exchange the positioner tips in accordance with the types. For the small-sized positioner tips, there is aced of exchanging them individually, such problems are presented that four times of working are needed for exchanging four positioner tips individually, the working is difficult to perform. Further, it is disadvantageous to switch over to an automatic exchange process and so forth.